Production of nitrogenous heterocyclic compounds



Patented May 16, 1944 "BODUCTION OI NITBOGINOUS mano- CYCLIO com'omms mmin. wares. m names. and Oskar Ilester, DessaI-Ialdeburg, Germanyvestedinthediienl'ropertyfllstodian NeDra Applies rialNo. 1.2.

Our present invention relates to nitrogenous heterocyclic compounds andmore particularlyto the production of intermediate products for thepreparation of dyestuffs especially cyanine dyestuffs.

We have found that salts of nitrogenous hetwherein Z stands for a groupof molecules necessary to complete a 5- or 6-membered ring usual incyanine dye art as, for instance, indoline, oxazole, thiazole,selenazole, oxazoline, thiazoline, selenazoline; pyridine, lepidine,imidazole, quinoline or thiodiazole; these heterocyclic radicals maycarry substituents such as alkyl, aryl, benzyl. phenylene, naphthyleneand substituted phenyls or heterocyclic radicals or may be condensedwith aromatic or heterocyclic rings: R1, Ra stand for alkyl or aralkyl,and X stands for an anionic acid radical as, for instance, Cl, Br, 1,C104, S04, SOsCHa, SOaCzHs, SO3CsH4.CHs, are obtained by reactingheterocyclic 2 (or 4) -methene-w-aldehydes of the formula:

- toluene, or xylene may be used as solvents. The

phosphorus pentasulflde is used in such an amount that at least 1 molthereof is applied to 1 mol of aldehyde. The thioaldehyde is obtained byconcentrating the reaction liquid or precipitating, for instance, withbenzene of methylisoheptane. The thioaldehyde is condensed withalkylhalides or reactive alkyl esters. This reaction may be accomplishedby reacting the al- EGG-M22 1 locum (clue-24st kylating agents and thethioaldehyde, if necessary in the presence of a solvent as, forinstance, methanol or benzene. As slkylating agents alkylbromide,alkyliodide, alkyisulfate or alkyltoluenesulfonate are, for instance,suited.

The compounds prepared by the process of the present invention arevaluable intermediate products in the preparation of dyestuffsespecially cyanine dyestuffs. Theys'eadily react with active methyleneor methyl groups with the formation of merocyanines or polymethinedyestuffs. The dyestuffs derived from these intermediate products areobtained in a purer form and with a better yield than they are byprocesses hitherto known. Owing to the reactivity of the intermediateproduct it is also possible to cause such compounds containing methyleneor methyl groups to react as have not hitherto been capable of formingdyestuffs.

' The more detailed practice of the invention is illustrated by thefollowing examples. There are, of course, many forms of the inventionother than these specific embodiments.

Example 1 so are added. The whole is boiled for two hours and filtered.The filtrate is clarified with charcoal, concentrated and precipitatedwith benzine. Melting point 110-111 C.

21 g. of the thioaldehyde thus prepared are 85 dissolved in 100 cc. ofmethanol and mixed with cc. of dimethylsulfate at 50 C. After cooling100 cc. of an aqueous sodium perchlorate solution of 20% strength isadded thereto. 28 g. of a compound of the following formula with amelting point of 225 C. crystallize out:

Example 2 l.1.3.fi-tetramethylindolin-2-methene-u-aldehyde is reactedwith phosphorus pentasulflde in the manner as described in Example 1. Ifthe thioaldehyde thus obtained and having a melting point of 199-201 C.with decomposition is treated with dimethylsulfate, a reaction producthaving a melting point of 191 C. and the following formula is produced.

HaC- CH:

. Example 3 1.1.3-trimethyl-6-methoxyindoline-2-metheneii-aldehyde istreated in the manner as described in Example 1. The thioaldehydeobtained melts at l'l0-l'72 C. The dimethyl sulfate addition product istreated in the manner as described in Example 1. It then melts at 225 C.with decomposition and has the following constitution:

H1500- CH;

Example 4 3 ethyl benzselenazoline-2-methene-w-aldehyde is reacted withphosphorus pentasulfide in the manner as described in Example 1. Theoily reaction product is treated with dimethylsulfate and precipitatedwith sodium perchlorate. The resulting product melts at 200 C. and hasthe following constitution:

Example 3 ethyl-benzthiazoline-Z-methene-w-aldehyde is transformed intothe thioaldehyde in the manner as described in Example 1. The reactionproduct is treated with dimethylsulfate and precipitated with sodiumperchlorate. The resulting product melts at 178 C. and has the followingformula:

150 cc. benzene and mixed with 1%; mol of dimethylsulfate.

After some time an addition compound having a decomposition point of143-145" C. and the following formula crystallizes out.

JT-CHg N --oH=oH-s-om 5 040m" CH:

Example 8 The addition compound of Example 7 is dissolved in water andmixed with an excess of an aqueous potassium iodide solution of 20%strength. A compound having a decomposition point of 226-22'7 and thefollowing constitution crystallizes out:

0 cm --C -CH:

'CH=CHSCH; N. CHs

Example 9 The addition compound of Example 7 is dissolved in water andmixed with an aqueous ammoniumthiocyanate solution of 20% strength. Acompound with a decomposition point of 193- 196 C. and having thefollowing formula crystallizes out:

OH: C CHa CCH=CHS-CH| BON- N CH:

Example 10 1.1.3 trimethylindoline-2-methene-w-aldehyde is transformedinto a thioaldehyde in the manner as described in Example 1.thioaldehyde are dissolved in cc. of methanol heated to 50 C. 35 cc. ofdiethylsulfate are then added to the solution whereupon the mixture iskept at 50 C. for 5 minutes. After cooling to 0 C. cc. of a sodiumperchlorate solution of 20% strength is added thereto. A compound of thefollowing constitution crystallizes out:

(J-CH:

O'CH=CHS--C:Hl 0104 N (all: We claim: 1. A process for producing saltsof nitrogenous heterocyclic compounds substituted by an 0-alkylmercaptoethane group in a position selected from the groupconsisting of aand v-positions which process comprises reacting aheterocyclic methene-w-aldehyde selected from the class consisting ofZ-methene-w-aIdehyde and -4-methene-w-aldehyde of the following generalformula:

p=cH-on=o wherein 2 means a group of molecules necessary tocomplete aring usual in cyanine dye art, said ring being selected from the classconsisting of 5- 21 g. of theand 6-membered rings, and R1 means analkyl, in a solvent with phosphorus pentasulfide and treating the thusresulting product with a compound selected from the class consistin ofalkyl halides and alkyl esters.

2. A compound of the following formula:

wherein Z means a group of molecules necessary to complete a ring usualin cyanine dye art, said ring being selected from the class consistingof and S-membered rings, R1, R2 mean an alkyl, and X means an anionicacid radical.

3. A dyestuff of the following formula:

6. A process for producing salts of nitrogenous heterocyclic compoundssubstituted by an malkylmercaptoethene group in a position selected fromthe group consisting of s -positions which process comprises reactingone mol of a heterocyclic methene-w-aldehyde selected from the classconsisting of 2-methene-w-aldehyde and 4- methene-w-aldehyde of thefollowing general formula:

wherein Z means a group of molecules necessary to complete a ring usualin the cyanine dye art, said ring being selected from the classconsisting of 5- and 6-membered rings, and R1 means an alkyl group, in asolvent with at least one mol on phosphorus pentasulfide and treatingthe resulting product with a compound selected from the class consistingof alkylhalides and alkylesters.

7. A process for producing salts of nitrogenous .heterocyclic compoundssubstituted by an aralkylmercaptomethene group in a position selectedfrom the group consisting of uand positions which process comprisesreacting a heterocyclic methene-w-aldehyde selected from the classconsisting of 2-methene-w-aldehyde and 4-methene-u-aldehyde with thefollowing general formula:

I }'J=CHCH=O wherein Z means a group of molecules necessary to completea ring usual in the cyam'ne dye art, said ring being selected from theclass consisting of 5- and G-membered rings, and R1 means an alkylgroup, in a solvent with phosphorus pentasulfide and treating theresulting product with a= compound selected from the class consisting ofalkylhalides and alkyl esters in the presence of a solvent selected fromthe group consisting of methanol and benzene.

8. A process for producing the nitrogenous heterocyclic compound of thegeneral formula:

which comprises reacting1-1-3-6-tetramethylindoline-2-methene-w-aldehyde with phosphoruspentasulflde and treating the resulting product with dimethyl sulfate.

9. A process for. producing the nitrogenous heterocyclic compound of thegeneral formula:

| CIHA which comprises reacting 3-ethyl-benzselenazoline 2 methene waldehyde with phosphorus pentasulfide, treating the reaction productwith dimethylsulfate and precipitating the resulting product with sodiumperchlorate.

' 10. A process for producing the nitrogenous heterocyclic compound ofthe general formula:

which comprises reacting 3-ethyl-benzthiazoline- Z-methene-w-aldehydewith phosphorus pentasulflde, treating the reaction, product withdimethylsuliate, and precipitating the resulting product with sodium.perchlorate.

, KARL KUMETAT. r v OSKAR RIES'I'ER.

